First disclaimer: I do not want this for homework. I simply want an answer. Nao, what I've seen, a single halogen can get into a 0 oxidation state combining with itself. Now....could an inorganic ion have a total 0 by combining with itself? Could a SO4 join with another and create an (SO4)-(SO4), like a self sulfate? For now, I have heavy evidence suspecting a big, huge 'NO!' and comments sending me to pay attention to my Chem class. But, "Be brave, the bravest ever.". So, what do our Chem pros think about a self sulfate or self nitrate and relative compounds?